A China-based cyberespionage gang has been linked to the infiltration of networks belonging to Telvent Canada, a major industrial control system company, in a case that some experts warn could facilitate creation of a dangerous cyberweapon.

The cyberspies, thought to be from a gang that security researchers call the "Comment Group" or sometimes the "Shanghai group," slipped past a corporate firewall, installing malicious software on the network – then snatched project files related to one of Telvent's major software products, according to KrebsOnSecurity, a cybersecurity blog that first reported the breach Wednesday.

As cyberespionage hacks that become public go – Google created a furor when it said it had been hacked by Chinese cyber spies in early 2010 and at least some of its vital source code had been stolen – it's been a relatively low-key news event so far.

The Telvent hack became public Wednesday on the cybersecurity blog and was later confirmed by Telvent's parent, Paris-based Schneider Electric.

"Telvent is actively working with law enforcement, security specialists and its affected customers to ensure the breach has been contained," Schneider Electric said. Just this month, Telvent announced a new relationship with Foxboro, Mass.-based Industrial Defender, a control systems security company.